>What if they were modified with a piece of hardware broadcasting its location to an API, and a correlating phone app using a push notification or voice alert to let the user know they are approaching.

You could use a beacon attached to a telephone pole, this is just some random idea, that will broadcast the location and push notifications. Or something in that nature, because I know retailers do this when you walk by a certain section and you have their app you will get a notification. So for public safety you could just have a app and if there is a crime that was reported, like a shooting, if you are within a certain block radius you get a notification.

This is something that I have thought about especially living in Philadelphia, constant crime is going on. I don't know what I am walking into or riding my bike into. It would be awesome to have updated information like this.